A scientific team led by Professor Zhou Yang at Southeast University (China) has conceived a novel type of cement enriched with hydrogel, capable of generating and storing electrical energy from heat.
This discovery, recently published in Science Bulletin, redefines the limits of cement-based thermoelectric materials, providing an unprecedented solution for the infrastructures of smart cities.
The key to this innovation lies in biomimetics, that is, in replicating the internal structure of plant stems, which have organized layers that optimize fluid and nutrient circulation. By applying this principle, scientists managed to increase ionic mobility, solving one of the most critical limitations of conventional cement.
High thermoelectric efficiency and integrated storage
The developed material achieves a Seebeck coefficient of −40.5 mV/K and a figure of merit (ZT) of 6.6×10⁻², values that represent a substantial improvement over similar materials. In practical terms, this means greater efficiency in converting heat into electricity, essential for applications in urban infrastructures.
In addition to generating energy, this thermoelectric cement also functions as an energy storage system, enabling its use in roads, bridges, and smart buildings. These structures could power sensors, monitoring systems, and wireless networks without the need for external energy sources.
The multilayer design maximizes the migration of hydroxyl ions (OH⁻) through the hydrogel, while calcium ions (Ca²⁺) interact with the cement, generating an enhanced thermoelectric effect. This configuration, furthermore, strengthens the material’s mechanical resistance, ensuring its viability in real constructions.
A step towards sustainability in construction
This development has enormous potential for global sustainability, as it:
- Harnesses ambient or waste heat to generate energy, reducing dependence on fossil fuels.
- Converts passive infrastructures into active energy sources, crucial in urban areas with high population density.
- Minimizes the use of disposable batteries by providing direct power for sensors and integrated devices.
- Promotes a circular economy, ensuring that construction materials not only fulfill their structural function but also generate and manage energy.
- Reduces the environmental impact of cement, one of the most polluting materials on the planet, by giving it a second ecological utility.
This technology represents a key advancement towards more resilient, efficient, and autonomous cities, aligning with global sustainability and energy transition goals.
